Pass a variable by reference from Angular2 template

Question

Let's say I have a variable called isVisible. And I have a method called

ReverseVariable(variable: boolean)
{
   variable = !variable;
}

I want to call this method from a template like

<button (click)="ReverseVariable(isVisible)"></button>

I want to give it isVisible in the parameters and have isVisible reverse itself. Something like the following example is not an option

ReverseVisibility()
{
  this.isVisible = !this.isVisible;
}

Is there any way that I can pass the variable by reference?

Is isVisible a property of the component? Do you say that this.isVisible = !this.isVisible is not an option because the variable name needs to be dynamic or because the variable doesn't belong to the this context? — BeetleJuice
– BeetleJuice, Commented Oct 24, 2017 at 13:29
It's not an option because I have way too many isVisible variables and with my last example, I will need a method for every one of them which is not great. It only clutters my component. — P_Andre
– P_Andre, Commented Oct 24, 2017 at 13:35

LLai · Accepted Answer · 2017-10-24 13:32:43Z

5

Not with a primitive data type like a boolean. What you could do is make a non-primitive like an object

isVisible = {
    flag: true
}

Then toggle that in your function

ReverseVisibility(isVisible)
{
   isVisible.flag = !isVisible.flag;
}

answered Oct 24, 2017 at 13:27

LLai

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